I've been using the Zork with Pentax Glass for several years, many of which I purchased at KEH. I like the fact I can test and send it back if I don't like it. Hurry on these lenses, once the 645D comes out there will be fewer around at more money. I use 35 fa, 45 6x7 with adapter, 55 2.8 A, 75 2.8, 105 2.4 6x7, 120 smc macro all very good lenses. Pentax should be coming out with a new wide but haven't announced it yet. I use the set up on the 1ds3 and 5d2.